This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section.
The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:
3GPP third generation partnership project
AOA angle of arrival
AP access point
CQI channel quality indicator
DCA discontinuous carrier activation
DL downlink (from base station to UE)
EMS element management system
eNB or eNodeB evolved Node B (e.g., LTE base station)
E-RAB E-UTRAN radio access bearer
ES energy savings
E-UTRAN evolved UTRAN
GBR guaranteed bit rate
hetnet heterogeneous network
HO handover
ID identification
IE information element
LTE long term evolution
MCS modulation and coding scheme
MDT minimization of drive test
MIMO multiple input-multiple output
MME mobility management entity
NSN Nokia Siemens Networks
O&M operations and maintenance
PH power headroom
PRB physical resource block
QCI QoS class identifier
RACH random access channel
RAN radio access network
RAT radio access technology
Rel release
RF radio frequency
RI rank indicator
RLF radio link failure
RNL radio network layer
RSRP reference signal received power
RSRQ reference signal received quality
RRM radio resource management
RRC radio resource control
Rx reception or receiver
SINR signal to interference plus noise ratio
SRS sounding reference signal
TA time alignment
TS technical standard
TR technical report
Tx transmission or transmitter
UE user equipment
UL uplink (from UE to base station)
UTRAN universal terrestrial radio access network
QoS quality of service
An Energy Savings (ES) method via deactivating unneeded eNB cell(s) has been a supported functionality in LTE since Rel-9. 3GPP TS 36.423 V9.6.0 (2011-03), section 8.3.11 (Cell Activation) provides stage 3 details for the X2 application protocol (X2AP) including the Cell Activation procedure used to request to a neighboring eNB to switch on one or more cells, previously reported as inactive due to energy saving reasons. 3GPP TS 36.300 V11.0.0 (2011-12), provides the Overall E-UTRA and E-UTRAN description where section 22.4.4.2 (“Solution description”), currently contains the following text regarding support for Energy Savings:
“All informed eNBs maintain the cell configuration data also when a certain cell is dormant. ENBs owning non-capacity boosting cells may request a re-activation over the X2 interface if capacity needs in such cells demand to do so. This is achieved via the Cell Activation procedure.”
Cell re-activation occurs when “capacity needs demand to do so”. But there may be other needs besides capacity needs at the non-capacity boosting (e.g., coverage) cell that may demand reactivation of a cell.